This invention relates to a feeding system for feeding crop material to a cutterhead, for example in a forage harvester, and more particularly to an improved feed roll assembly for such a machine.
A typical forage harvester feed roll assembly includes opposed upper and lower pairs of feed rolls driven in such directions that crop material gathered from a field by a forward mounted header and delivered to the inlet of the feed roll assembly, that is to the "bite" of the opposed upper and lower forward or upstream feed rolls, is conveyed rearwardly in an approximately horizontal mat between the upper and lower pairs of rolls to a cutterhead for reduction of particle size.
When harvesting certain materials, significant crop loss may occur through particles of material passing downward between the delivery outlet of the header adjacent the feed roll assembly and the forward lower roll or between the forward and rearward lower rolls. This type of loss occurs particularly in grain sorghum head cutting, ear corn and dry whole-plant corn and similar harvesting operations. It is known to reduce such losses by providing a floor or shield extending from the delivery point of the header between the upper and lower feed roll pairs and terminating adjacent the rear feed rolls to cover the gaps adjacent the forward lower roll. However, with such a shield in place, the efficiency and capacity of the feed roll system is seriously reduced because only two active feed rolls are available to feed the material and because of friction between the moving material and the fixed shield.